SRINAGAR, INDIA—Heavy monsoon rains have inundated Kashmir, causing flash floods and landslides that left at least 80 people dead on the Indian and Pakistani controlled sides of the disputed Himalayan region.

Another 36 people were killed in Pakistan’s eastern Punjab region when their roofs collapsed Thursday, said Ahmad Kamal, a spokesperson for Pakistan’s National Disaster Management Authority. The agency said it expected “exceptionally high floods” over the coming weekend.

The NDMA said Pakistan’s main rivers were swollen and that flash floods and heavy rains had damaged hundreds of homes. Officials confirmed that 30 people and three soldiers have died in Pakistan-administered Kashmir over the past 24 hours.

Shantmanu, an Indian official who goes by only one name, said 47 people had died in Indian-controlled Kashmir, including five whose bodies were pulled from the rubble of a home that collapsed in the Poonch region. Three other people, including a paramilitary soldier, were washed away when a bridge collapsed in a separate incident.

Kashmir is divided between India and Pakistan and claimed by both. They have fought three wars, two of them over control of Kashmir, since winning independence from Britain in 1947.

On Thursday a bus filled with more than 50 members of a wedding party on the India-administered side was swept away by a swollen stream. Five bodies have been recovered while four of the passengers swam to safety. The fate of the others is not yet known.

The region has been hit by its worst monsoon flooding in more than two decades. Power and telephone links have been cut in many areas and supplies of clean drinking water have been hit, Indian officials said.

Soldiers and rescue workers used boats to move thousands of people to higher ground. Public address systems in mosques warned people in the worst-hit neighbourhoods to move to safety. Parts of Kashmir’s main city of Srinagar were also flooded.

Indian officials said at least 100 villages across the Kashmir valley were flooded by streams and rivers, including the Jhelum river, which was up to two metres above its danger level.

At least 300 rescuers with boats and sophisticated search equipment from India’s National Disaster Response Force arrived in the region, according to Rohit Kansal, a civilian official.

The flooding inundated homes, cut off neighbourhoods, and damaged bridges across the state. Indian officials said southern areas of Kashmir suffered massive flooding and most of the federal rescuers were sent to that area to help rescue efforts.

The state government on the Indian-controlled side said it was setting up rescue shelters and had budgeted 200 million rupees ($3.6 million) for relief and rescue efforts.

The Pakistani military, meanwhile, said troops using helicopters and boats rescued 368 people from flood-affected areas near Islamabad on Friday.